Genuine Bosch coupling (part 2615294309) — a flexible, ribbed plastic sleeve that links the motor shaft to the accessory/output shaft on rotary multi‑tools, absorbing torsional shock and preventing direct metal‑to‑metal wear.

Listed for Dremel / Bosch 395 series multi‑tools (models F013039504, F013039510, F013039511, F013039512, F0130395CA / Type 3 and related variants), making it the correct replacement when the original coupling has cracked or slipped.

Compact in size — roughly 25 × 13 mm (approx. 1.0 × 0.5 in) — the part is a short, internally bored sleeve that slips over the shafts; failures are typically age‑related cracking or torque overload and it’s an inexpensive, quick restore to smooth operation.

Available single or in multi‑packs as a genuine Bosch power tool spare parts item, it’s a straightforward replacement you can fit with basic hand tools — a useful item to keep with other essential power tool parts for repairs.